Laravel 多级关系答案

【问题标题】：Laravel multi level relationshipLaravel 多级关系
【发布时间】：2022-01-01 03:50:00
【问题描述】：

我想创建显示 class_meets 信息的视图有关其他信息，我想显示表主题中的主题名称已经在尝试 hasOneTrough、hasManyTrough 和 belongsToMany 但这就像函数只显示从主题到 class_meets，而我需要的是相反的

想在 ClassMeet 模型上添加一些功能

这是我的清单模型：

主题

class Subject extends Model
{
    use SoftDeletes;
    public $table = 'subjects';
    protected $dates = ['created_at', 'updated_at', 'deleted_at'];
    protected $fillable = [
        'subject_name'
    ];
}

常规

class Routine extends Model
{
    use SoftDeletes;
    public $table = 'routines';
    protected $dates = ['created_at', 'updated_at', 'deleted_at'];
    protected $fillable = [
        'academic_year_id',
        'subject_id',
        'classes_id'
        'day',
        'start_time',
        'end_time',
    ];
}

课堂聚会

class ClassMeet extends Model
{
    use SoftDeletes;
    public $table = 'class_meets';
    protected $dates = ['created_at', 'updated_at', 'deleted_at', 'date'];
    protected $fillable = [
        'routine_id',
        'date'
    ];
}

【问题讨论】：

标签： php laravel eloquent

【解决方案1】：

hasOneTrough，hasManyTrough 在这种情况下不起作用。

你需要添加belongsTo关系到ClassMeet,Routine。

class ClassMeet extends Model
{
    use SoftDeletes;
    public $table = 'class_meets';
    protected $dates = ['created_at', 'updated_at', 'deleted_at', 'date'];
    protected $fillable = [
        'routine_id',
        'date'
    ];

    public routine(){
         return $this->belongsTo('App\Routine','routine_id','id')
    }
}

例程模型是这样的

class Routine extends Model
{
    use SoftDeletes;
    public $table = 'routines';
    protected $dates = ['created_at', 'updated_at', 'deleted_at'];
    protected $fillable = [
        'academic_year_id',
        'subject_id',
        'classes_id'
        'day',
        'start_time',
        'end_time',
    ];
     public subject(){
         return $this->belongsTo('App\Subject','subject_id','id')
     }
}

现在你可以通过例程获得主题了。

ClassMeet::with('routine.subject')->get();

【讨论】：